Electronic behavior of native oxide films on Ti and TiN during 90-day immersion in electrolytes with different pH levels

• 作者: Amir Poursaee Golnaz Najaf-Tomaraei Marian S.Kennedy
• 来源期刊: 稀有金属（英文版）
• 年，卷（期）: 2021,（3）
• 所属期刊栏目: ORIGINAL ARTICLES
• 页码范围: 582-589
• 页数: 8页
• 语种: 英文

摘要

This work presents the electronic behavior of Ti and TiN thin films when exposed to electrolytes with pH levels of 2,7 and 13 for 90 days.Staircase potentio-electrochemical impedance spectroscopy tests were performed on the 100-nm Ti and TiN monolithic films,and Mott-Schottky analysis of these tests was used to determine the films' semiconductive behavior and changes in the donor/acceptor density.In addition,the flat-band potential of each film's surface oxide was also characterized.No attempt was made to control oxide formation,and therefore,these tests reflected the native surfaces of these films.While the TiN films exhibited n-type semiconductivity in all electrolytes,the Ti films only showed n-type behavior in the acidic (pH =2) and neutral (pH =7) electrolytes.The semiconductivity of the Ti films transitioned to p-type during exposure to the basic electrolyte (pH =13) after reaching 60 days.Furthermore,there was a significant increase in the donor densities for both Ti and TiN films when immersed in the basic electrolyte relative to the acidic and neutral electrolytes.